Loader construction



Sept. 12, 1939. J. L. CLARKSON LOADER CONSTRUCT ION 4 Sheets-Sheet 1 Filed Sept. 20, 1935 'IIIIIIIIIIIIIIIII c/OHN L. CLAEKSON, M5

Sept. 12, 1939. J L. CLARKSON 2,172,360

LOADER CONSTRUCTION Filed Sept. 20, 1935 4 sheets sheet 2 JOHN L. CLAEKS 0N,

p 1939. J. CLARKSON LOADER CONSTRUCTION Filed Sept. 20, 1955 4 Sheets-Sheet 4 doH/v L. CLAEKSON,

Patented Sept. 12, 1939 UNITED STATES PATENT OFFICE 14 Claims.

This invention pertains to loading machines and more particularly to that type of loading machine which is used for loading coal in coal mines, or for similar work where heavy materials have to be loaded.

In the operation of certain types of such loading machines, the material is gathered from the ground or from the floor of the mine by means of appropriate gathering mechanisms and is moved thereby onto a conveyor extending upwardly and rearwardly, which operates to move the coal rearwardly and elevate it at the same time so as to pass it over the loading machine. In the usual construction, this elevating conveyor delivers the material to a second conveyor, which in turn loads it onto mine cars or other conveyances for transporting it to a suitable point of delivery. In a successful type of loading machine, the forward end of the elevating conveyor has mounted there- 0 on a pair of gathering mechanisms, one on each side of the conveyor and both extending somewhat forwardly thereof, so as to gather the material from the floor and move it up onto the conveyor. In loaders for handling heavy materials, these gathering devices must be capable of digging under a pile of heavy materials, and the operation is usually such that the head of the machine, including virtually the entire gathering mechanism, is eventually worked under the pile of material, so that the weight of the material rests upon the gathering head of the machine.

In prior constructions, the gathering devices, which usually operate in synchronism with each other, are connected by a cross-shaft, which runs transversely of the conveyor, usually just below the gathering devices, and connects the two devices rigidly together. The power which drives the gathering devices is delivered to this shaft at one side of the conveyor. In this arrangement, the power must be transmitted to the gathering device on the other side of the conveyor through this shaft. Difficulties have been encountered with this structure. As the body of the gathering conveyor is more or less flexible, being a long,

extending arm, the weight of the material resting upon the gathering head during operation may have a tendency to flex the body of the conveyor.

This might happen, for instance, when one side of the gathering shoe rides up on an elevated portion of the floor while the other side rests in a depression. With such flexure of the body of the conveyor, there is a tendency to throw the cross-shaft out of line; consequently, there might be binding of this shaft in its bearings or excessive stresses on the gears connecting it to the gathering devices. Excessive stresses often result in broken gears or broken shafts and occasionally the elevator body itself gives away.

One of the objects of this invention is to provide a loader structure and particularly a drive for the gathering devices which will overcome these objections.

Another object is to provide a drive by which the separate gathering devices may be driven independently of one another.

Another object is to provide means whereby, in addition to such independent drive of the separate gathering mechanisms, flexible cross connections may be provided whereby power may be transmitted from one gathering device to the other, so that in case of uneven loading they may help each other out.

Another object is to provide a conveyor body structure re-enforced or stiffened so as to resist twisting stresses.

Further objects will appear from the following description taken in connection with the accompanying drawings, in which- Figure 1 is a side elevation of the forward end of a loading machine here involved, of a preferred embodiment of this invention showing the front conveyor and gathering mechanism together with driving means therefor constructed and arranged in accordance with this invention;

Figure 2 is a plan view of Figure 1 with slight modification, with parts broken away to show the sub-structure but showing another embodiment;

Figure 3 is a detail section, considerably enlarged, taken on line 3-3 of Figure 1 and showing the preferred embodiment;

Figure 4 is a view similar to Figure 3, showing the construction and the flexible cross-connection between the gathering devices of the embodiment shown in Figure 2; I

Figure 5 is a detail section, somewhat enlarged, taken on line 5-5 of Figure 1 and common to both embodiments;

Figure 6 is a perspective detail of the body structure common to both embodiments; and

Figures 7 and 8 are views similar, respectively, to Figures 2 and 1, illustrating still another embodiment of the invention.

The machine selected for the purpose of illustration in the drawings is of the same type as that illustrated in the patent to John L. Clarkson, No. 1,904,355, issued April 18, 1933, to which reference may be had for further details of structure and operation.

Referring now to the drawings, I designates a supporting bracket extending forwardly from a traveling truck upon which the entire machine is mounted; this bracket I therefore forms a part of the machine body. Such a truck may be arranged to travel on a track or on a caterpillar tractor,- or in any other suitable manner, adapted to convey the machine to its place of operation and to provide for moving it forwardly and backwardly into and out of the pile of material to be loaded. Swiveled for lateral movement at on a cross web of the bracket I is a forwardly-extending bracket 8. movement relative to the bracket 8, is a forwardly extending boom bracket 3, which carries the elevating conveyor indicated generally at 4. This hinged connection provides for raising and lowering the head or gathering end of the conveyor 4 so as to be able to operate on material at different levels. The boom bracket 3 may move laterally with the bra'cket'B on' the swivel 80 so as to enable the head to be swung laterally in order to reach materials on either side of a track on which the truck may be operating. As the present inventionis not primarilyIconcerned with these portions of structure, the same will not be further described here, but reference may be had to the above-mentioned patent for further description of these details.

a The conveyor 4 is'mounted on the boom bracket 3 by means of uprights 5 and 6, by means of which the rear of the conveyor 4 is rigidly mountedon the boomi bracket 3.; The boom bracket 3, in turn; is mounted on the hinge 2 at its rear end and'at its forward end ona pair of hydraulic jacks 1.. The jacks 1, in turn, are supported on the bracket 8, 'only 'part of which" is visible in Figure 1 as it extends under and Within the boom bracket 3." It will be seen that this structure provides that by operating the hydraulic jacks I, the boombracket 3, and with it the conveyor 4, maybe elevated or lowered; The part 3 which is thus mounted for vertical and lateral movement forms what may beterrned a boom extending forwardly from the body of the machine.

'Mounted on the forward end of the boom which carries the conveyor 4, so as to overlap the same, is a gathering head indicated generally by the numeral, 9 and comprising side parts and a front part having its rear terminus at 90. This head extends generally'over the conveyor but is notched out 'at its upper portion as to uncover the body portion IIlof the conveyor 4; .Mounted on the head '9 and extending along the sides thereof is a pair of gathering devices, each'indicate'd generally by the numeral II. Each of these gathering devices comprises a gathering chain I2 armed with a series of picks or gathering arms shown in conventional form at I3. The chains I2 are driven'so as to travel in orbital path over an upper sprocket I4 and a lower sprocket I5. This travel operates to move the picks I3 in a corresponding orbit, passing upwardlyover and along the conveyor 4, as indicated by the arrows in Figure 2.

Referring now to Figures 1 and 3, in order to drive the chains I2, each sprocket I4 is mounted on an' upright shaft I 6 mounted in bearings I"! in asuitable housing I8 carried by the conveyor 4. The lower end of the shaft, I6 carries a bevel gear I9 meshing with a similar gear 20 on a horizontal stub shaft 2I, also joumaled in suitable bearings 22 .in'the' housing I8. The shaft 2I also carries aasprocket' 23, by means of which this train of mechanism is driven- The shaft I6 is usually not vertical but stands in a position substantially Hinged at 2, for vertical perpendicular to the head 9, as may be understood by reference to Figure 1. These trains of mechanism, such as shown in Figure 3, provide separate gearings for driving the separate gathering chains I2. By this arrangement each gathering chain is provided with its own gearing for driving the same and, as shown in Figure 3, the gearing which drives each chain is independent of that of the other chain. Accordingly, these separate gearings are capable of movement relative to each other when the gathering head or the conveyor body I0 is distorted by uneven loading or other cause. This relative movement is permitted by virtue of the fact that the shaft 2I is a short stub shaft and there is a separate one of these for each gearing. The advantage of this arrangement is in the separation of the gearings on the opposite sides of the head. In prior structures of this type the drive of the gathering chains has been through a shaft extending clear across the head and connecting rigidly the trains of gearing which drive the separate gathering chains. Such a cross shaft is subj'ectto bending or other'distortion when the 'head or body is Warped or twisted by uneven operating conditions and such distortion of the shaft throws the driving gears, such as the bevel gears I9 and 20, out of proper alignment so that they do not mesh accuratelywith each other. This, of course, not only 'renders the action of the gears uncertain but is 'liableto cause breakage and in fact such breakage is frequently experienced with such a rigid'cross shaft construction.

The'sprocket 23 on each side is driven by a flexible chain 24 from a cross-shaft 25; The cross-shaft 25 is mounted on the conveyor structure4, as will be seen from Figure Lsubstantiallyin rear of the forward portion of the conveyor 4'. The particular purpose of so positioning this shaftwill'be more fully explained hereinafter. The shaft 25'carries a sprocket 26 on each end thereoffand there is a direct 'primary driving connection in the form of a flexible driving chain 24 on each 'side of the conveyor 4 so that .each of the gathering devices II is driven by a separate flexible connection from the shaft 25. Each connection 24 normally supplies the entire power required by its own gathering device II. The shaft 25 may be driven by a chainZI from a shaft 28, which; in turn, may be driven by gear 29 from'the shaft of a suitable motor30.

It will be noted that this arrangement provides separate driving connections, such as the chains 24, extending forwardly from the shaft 25 to the gathering devices. The shaft 25, being mounted on the frame of the conveyor 4 at a portion thereof spaced rearwardly from the forward part or that part "on which the gatheringdevices are mountedfis usually subject to but little flexure under adverse loading conditions, which would be liable to twist or warp the frame of the conveyor 4'. Since the connections 24 are flexible, they may accommodate themselves readily to such flexure as may occur between the shaft 25 and the forward end of theconveyor.

In order further to re-enforce' the frame of the conveyor 4 against flexure and to stiffen the same so as to avoid distortion of the supports of the shaft 25, that portion of the frame of the conveyor'4 between the shaft 25 and the gathering devices is "substantially re-enforced.

The conveyor proper consists of a pair of chains 3I'slidable on the body I0 and carrying between them a series of flights 32 adapted to move the material upwardly over the body ID. The chains 76 3| are of the endless type, passing over sprockets 33 at the upper and lower ends of the body l0 and suitable guide sprockets for the return portion of the conveyor, which passes downwardly underneath the body l0. Any suitable arrangement for guiding the conveyor chains may be provided, and as these are not a part of the present invention, they need not be described in detail. The chains 3| may be driven by sprockets 34 on the shaft 25 or by any other suitable means.

The body ID is preferably of channel form, on its upper side at least, so as to provide a trough along which the flights 32 may move so as to carry the material upwardly and guide the same in its travel. The chains and the flights are cut away in the middle of Figure 2 so as to show the body boom in section. In the embodiment illustrated, the body I0 is of I-beam form, laid with its web horizontal and its flanges extending upwardly and downwardly as shown in Figure 5, and also in Figure 3, so as to provide on the upper surface thereof a trough for carrying the material. In order to stiffen the body I U at the point between the gathering devices and the shaft 25, re-enforcing side plates 35 are integrally attached to the body In, as by welding or riveting. These plates are preferably attached on the outside of the flanges of the body l9 and have the form illustrated in Figures 1, 5 and 6. Integrally secured to the flanges of the body Ill and on the outside thereof are supporting angles 35. The angles 33 are mounted at an inclination with reference to the body ID, as may be seen in Figure 1. The purpose of this is to elevate the rear portion of the gathering devices ll so that the gathering arms l3 may rise out of the material as it is loaded onto the conveyor. The rear ends of the angles 36 rest in notches in the plate 35, as shown at 3'! in Figure 1. In order more effectively to reenforce this part of the structure, additional reenforcing plates 38 are placed so as to span the joint between the plates 35 and the angles 36 at the notch 31. These plates 38 are also integrally connected with the members 35, 36, and ID, as by welding or riveting.

It will be seen that this re-enforcing structure provides effective stiffening for that portion of the conveyor frame which is subject to the greatest twisting stresses under loading conditions where the loading head or shoe 9 is unevenly weighted with material or unevenly supported on the floor, or both. This re-enforcing not only protects that part of the conveyor frame which supports the shaft 25 from excessive distortion, but reduces to a minimum relative distortion between the sprocket 26 and the sprocket 23. Accordingly, any twisting of the frame is confined to the front portion of the conveyor and the flexibility of the driving connections is such that they are not disarranged by any normal amount of such distortion.

Referring now to Figures 2 and 4, which show another embodiment of this invention, in order to provide for positive drive of the gathering devices under any conditions of unequal loading, a sectional cross-shaft 39 may be provided, extending transversely just below the gathering head 9 at its rearward portion, replacing shafts 2| of Figure 3. This shaft may connect the sprockets 23 on opposite sides of the head as shown in dotted lines in Figure 2. The shaft 39 is made in two sections, which are joined at an intermediate point by a flexible coupling 40. The coupling 49 is preferably of the type adapted to provide for mis-alignment of the separate shaft sections in all directions. This shaft provides a transverse driving connection between the lower ends of the chain 24, which is flexible so as not to be disarranged by twisting of the conveyor body, and which is capable of transmitting power from any one of the chains 24 to the gathering device II on the opposite side of the machine. This. is of great advantage under uneven loading conditions, because the two chains 24 can help each other out and thus balance the load between them and equalize the load on the ends of the shaft 25. In Figure 4 similar parts are indicated by the same reference characters as in Figure 3.

By flexible as used in this specification and the appended claims is meant the property by which the parts may flex to change slightly the positions thereof to accommodate the operations described, as distinguished from the usual slight yielding of a rigid member under stress.

In the embodiment illustrated in Figures 7 and 8, a somewhat simplified structure is shown and one which is suitable for machines of lighter construction adapted for operation under less exacting conditions than are encountered in mine loading, although, with proper design, this structure may also be adapted to mine loading or heavy machines. In this structure, the driving chains 24 are dispensed with and the sectional shaft 39 is arranged to be driven directly by the elevator chains 3!. Suitable driving sprockets 4| may be mounted on the shaft 39 and each chain 3| is passed under the sprocket 4|, after passing over idlers 42 on both sides thereof as illustrated in Figure 8. As the chains 3| are driven from the main drive shaft 25, this construction provides a simple driving connection to the gathering mechanism by means of the conveyor chain.

In this embodiment also the side flanges of the trough H], where they pass under the gathering head, are provided with flaring rim plates 43. These plates are shown also in Figure 4. Similar flaring rim plates 44 may be provided along the sides of the trough l0 beyond the upper extremity of the gathering head. These rim plates may be welded to the trough and to the gathering head 9. As their upper edges flare outwardly, they provide a sort of hopper, adapted to guide material into the trough ID from the upper portion of the gathering head.

It has been found that, when loading certain types of small loose material, such as small coal, when the material is wet, it tends to adhere to the picks and may be carried along therewith to the upper portion of the gathering head. The general vibration of the machine eventually dislo-dges this adhering material, which then falls within the rim plates 43 and is guided to the conveyor. In the absence of such flared rim plates, it has been found that this material, when shaken off the picks, is liable to be deposited upon the upper part of the head 9 and is then caught by the picks in turning their upper turn and is swept off the gathering head. These flaring rim plates have been found to correct this difficulty.

It will be seen that this invention provides a structure whose effectiveness for loading heavy materials is greatly enhanced. By placing the main cross-shaft 25 rearwardly of the forward end of the conveyor, its supports are provided at the rear portion of the conveyor frame, which is of more rigid construction than the forward portion, and distant from the point of maximum distortion so that the possibility of misalignment of its bearings under unbalanced load is greatly reduced. The portion of the conveyor frame between the shaft 25 and the gathering devices is very materially stiffened by the plates and 38. This re-enforcement also tends to confine any twisting distortion to the forward end of the frame, where some slight flexibility must be permitted in order to avoid danger of breaking the parts. The driving connections between the shaft 25 and the gathering devices II are also flexible and are separate for the two sides of the machine. Accordingly, they are not affected by warpage or twisting of the body of the conveyor. Each gathering device may therefore receive full power and the driving devices act at full efliciency because there is no misalignment or other action which might tend to cause binding or excessive friction.

Uneven loading conditions are further provided for in the embodiment of Figures 2 and 4 by the sectional shaft 39, with its flexible coupling 40. This provides a flexible transverse connection between the chains 24 right at the gathering devices. This ties the two sides of the driving mechanism together in such. a way that, while each gathering chain receives power primarily from its own driving chain, power may be transmitted back and forth by means of the transverse connection 39-40, and the two sides may help each other out when necessary. The flexibility of this connection provides that this transfer may be made under all conditions of unequal load without danger of binding or similar trouble in the power-transmitting connection.

The embodiment of Figures 7 and 8 provide a simplified construction which may be used on lighter machines, such for instance, as may be used for loading gravel, broken stone or broken small coal in coal yards or for similar purposes. The simplified drive for the gathering mechanism renders the machine less costly to construct. The flexible connection may be used with these chains to equalize the load thereon. The flaring rim plates improve'the operation of the machine when handling small material'which is wet and thereby increase the range of usefulness 'cf 'the machine generally.

While this invention has been described as embodied in a unitary mechanism, it will, of course, be understood that certain individual features and sub-combinations thereof may be useful by themselves without reference to the complete combination. It is understood that the employment of such individual features and sub-combinations is contemplated by this invention and within the scope of the appended claims. It is further obvious that various changes may be made, within the scope of the appended claims, in the details of construction without departing from the spirit of this invention; it is to be understood, therefore, that this invention is not limited to the specific details showna'nd/or described.

Having thus described the invention, what is claimed is:

1. In a loader of the character described, having an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering devices mounted in laterally opposite relation to each other on the front of said conveyor; driving mechanism other than said conveyor for said gathering devices comprising, a separate flexible driving connection extending rearwardly from each of said gathering devices along said conveyor, means positioned rearwardly of the front portion of 'saidconveyor connected and operable to drive said flexible connections, and a flexible cross connection connecting said gathering devices adapted totransmit power from either of said flexible connections to the opposite gathering device;

2. In a loader of the character described, having an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering laterally opposite relation to each other on the front of said conveyor; driving mechanism other than said conveyor for said gathering devices comprising, a separate flexible drivingconnection extending rearwardly from each of said gathering devices along said conveyor, a cross driving connection extending transversely of said conveyor in rear of said gathering devices and connecting said flexible connections to drive said devices synchronously, a motor connected to drive said cross connection, and a flexible cross connection connecting said gathering devices adapted to transmit power from either of said flexible connections to the opposite gathering device.

3. In a loader of the character described, having an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering devices mounted in laterally opposite relation to each other on the front of said conveyor; driving mechanism for said gathering devices comprising, separate flexible driving chains extending rearwardly from each of said gathering devices along said conveyor, a motor connected to drive said chains, and a sectional cross shaft connecting said gathering devices having a flexible coupling inserted between the sections thereof adapted to transmit power from either of said chains to the opposite gathering device.

4. In a loader of the character described, having an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering devices mounted in laterally opposite relationto each other on the devices mounted in V front of said conveyor; driving mechanism other than said conveyor for said gathering devices comprising, a separate flexible driving connection extending rearwardly from each of said gathering devices alongsaid conveyor, 2. cross driving conlaterally opposite relation to each other on the front of said conveyor; driving mechanism for said gathering devices comprising, a separate flexible driving connection extending rearwardly from each of said gathering devices along said conveyor, means positioned rearwardly of the front portion of said conveyor connected and operable to drive said flexible connections, a flexible cross connection connecting said gathering devices adapted to transmit power from either of said flexible connections to the opposite gath} ering device, said conveyor having a channelshaped body provided with marginal flanges, and stiffening side members rigidly secured to said flanges between said gathering means and said driving means. i

6. In a loader of the character described, having an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering devices mounted in laterally opposite relation to each other on the front of said conveyor; driving mechanism for said gathering devices comprising, separate flexible driving chains extending rearwardly from each of said gathering devices along said conveyor, a motor connected to drive said chains, a sectional cross shaft connecting said gathering devices having a flexible coupling inserted between the sections thereof adapted to transmit power from either of said chains to the opposite gathering device, said conveyor having a channelshaped body provided with marginal flanges, and re-enforcing angle members along said flanges and secured integrally thereto and to said gathering means so as to stiffen said body against twisting.

7. In a loader of the character described, an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering means at the front end thereof, said conveyor having a channel-shaped body having upstanding marginal flanges and stiffening side members permanently secured to said flanges just in rear of said gathering means.

8. In a loader of the character described, an elevating conveyor rigidly sup-ported at its rear end and extending forwardly and downwardly and having gathering means at the front end thereof, said conveyor having a channel-shaped body having upstanding marginal flanges, an angle member permanently secured to a flange of said body to extend along said gathering means, and a stiffening plate permanently secured to said flange in prolongation of said angle member.

9. In a loader of the character described, an elevating conveyor rigidly supported at its rear end and extending forwardly and downwardly and having gathering means at the front end thereof, said conveyor having a channel-shaped body having upstanding marginal flanges, an angle member permanently secured to a flange of said body to extend along said gathering means, a stiffening plate permanently secured to said flange in prolongation of said angle member and a bridging plate spanning the joint between said stiffening plate and said angle and permanently connected to both.

10. A loading machine of the character described, comprising, a boom extending forwardly from the body of the machine and provided at its forward end with a gathering head which is subject to twisting stresses, a pair of gathering devices mounted on and extending respectively along the sides of said head, driving means mounted rearwardly of said head, gearings mounted on said head at the sides thereof and connected to drive said respective devices, said gearings being free for relative movement to accommodate twisting stresses of the head, and separate driving connections from said driving means to said respective gearings,

11. A loading machine of the character described, comprising, a boom extending forwardly from the body of the machine and provided at its forward end with a gathering head which is subject to twisting stresses, a pair of gathering devices mounted on and extending respectively along the sides of said head, driving means mounted rearwardly of said head, gearings mounted on said head at the sides thereof and connected to drive said respective devices, each of said gearings having a separate shaft free for movement relative the other to accommodate twisting stresses of the head, and separate driving connections from said driving means to said respective shafts.

12. A loading machine of the character described, comprising, a boom extending forwardly from the body of the machine and provided at its forward end with a gathering head which is subject to twisting stresses, a pair of gathering devices mounted on and extending respectively along the sides of said head, driving means mounted rearwardly of said head, gearings mounted on said head at the sides thereof and connected to drive said respective devices, said gearings being connected by a flexible coupling to permit free relative movement to accommodate twisting stresses of the head, and separate driving connections from said driving means to said respective gearings.

13. A loading machine of the character described, comprising, a boom extending forwardly from the body of the machine and provided at its forward end with a gathering head which is subject to twisting stresses, a pair of gathering devices mounted on and extending respectively along the sides of said head, driving means mounted rearwardly of said head, gearings mounted on said head at the sides thereof, each gearing having bevel intermeshing gears connected to drive said respective devices, said gearings being free for relative movement to accommodate twisting stresses of the head, and means for driving said gearings from said driving means.

14. A loading machine of the character described, comprising, a boom extending forwardly from the body of the machine and provided at its forward end with a gathering head which is subject to twisting stresses, a pair of gathering devices mounted on and extending respectively along the sides of said head, driving means mounted rearwardly of said head, a pair of upright shafts mounted on said head at the sides thereof and connected to drive said respective devices, a pair of horizontal shafts mounted respectively below said respective upright shafts and connected thereto by bevel gears, said horizontal shafts being free for relative movement to accommodate twisting stresses of the head, and chains connecting said driving means with said respective horizontal shafts.

JOHN L. CLARKSON. 

